Abstract: Objective To explore the application of online teaching of ultrasonic theory during the COVID-19 pandemic. Methods The standardized training of undergraduates, graduates and refresher doctors who have participated in the online theoretical teaching of ultrasound in the Peking University Third Hospital. Compared with the assessment results in previous years as the Objective index, the questionnaire was used as the subjective evaluation index. Results There was no significant difference between the experimental group and the control group. It is shown that 78.3% of learners belives that the online teaching method got better than the conventional offline teaching method. Conclusions The quality of online teaching is similar to that of conventional teaching mode but both trainers and trainees prefer the online teaching.

Key words: online teaching, teaching feedback, ultrasound medicine